The present invention relates to a method and apparatus for removing water from oil. More particularly, the present invention relates to a method and apparatus using super absorbent polymers to remove water from a water/oil emulsion such as a water/motor oil emulsion.
While the present invention is broadly applicable to a method and apparatus for removing water from a water/oil emulsion, it is particularly well suited for the removal of water from water/oil emulsions where the form of oil is one which is derived from petroleum, used as a lubricant in internal combustion engines, and is commonly referred to as “motor oil.” During service as a lubricant in an internal combustion engine, motor oil becomes contaminated with various contaminants, one of which is water. The presence of water in motor oil is generally undesirable and it is usually necessary to remove the water from the motor oil in order to further process or recycle the motor oil. Removal of water from used motor oil is difficult, however, because the mixture is often a stable emulsion which is hard to break.
Water is conveniently removed from motor oil by one of two general methods. One method for removing water from motor oil involves distilling the mixture. This method, however, has two disadvantages. Distillation processing involves heating the emulsion, which requires substantial time and energy, two commodities, which are becoming increasingly expensive. Furthermore, heating of motor oil tends to evaporate volatiles in the oil, which leads to environmental concerns and further expense. Another method for removing water from oil involves chemically treating the oil-water mixture to break the emulsion, allowing the mixture to separate into oil and water phases in a settling tank and then draining the water phase from the tank. However, this method also has certain disadvantages. The chemicals used to break the emulsion are relatively expensive. Also, this method requires substantial time for the separation of the water phase from the oil phase and usually also uses heating to speed up the process. In short, both known methods for removing water from motor oil are relatively expensive and time consuming, and there remains a need for an improved process and apparatus for removing water from oil.
Accordingly, the present invention provides a process and apparatus which employs relatively inexpensive and reusable superabsorbent polymers to break a water/oil or oil/water emulsion and separate the water from the oil by absorbing the water. The present invention substantially reduces the time and cost associated with conventional methods of removing water from oil and does not require heating of the oil which might cause volatiles to separate therefrom.
Further understanding of the present invention will be had from the following disclosure and claims taken in conjunction with the accompanying drawings.